120 ECONOMIC ESSAYS IN HONOR OF JOHN BATES CLARK 
Ricardian theory of rent has had less influence, more attention 
has been given to land as a factor in production, and at least 
the beginnings of classification of land are found in German 
economic treatises. 
The Complexity of the Land Concept. So long as land was 
considered as if it were one thing, a unit, and a thing producing 
an income of an entirely peculiar character, a development of 
land economies could not be expected. However, when we recall 
that the term land, as used by economists, means the forces of 
nature, so far as they have economic significance, 1t seems a 
little absurd to regard them all as belonging to one simple 
economic category or class. How diverse are the forces of nature! 
And what can we say about all these forces which have much 
scientific or practical value? Some things of real value, to be 
sure, can be said. Nevertheless, we cannot get very far scien- 
tifically or practically so long as we regard land as an undiffer- 
entiated whole. 
We can test this statement by calling to mind some of the 
popular discussions in regard to land. Public versus private 
ownership is much debated. But it is ridiculous from any point 
of view to say of land as a whole that it should be owned publicly 
or that it should be owned privately. We must first know of 
what kind of land we are speaking. Practically all agree that 
our city streets and rural highways should in general be publicly 
owned, and that privately owned toll roads are usually, though 
not always, an anachronism. Experts are for the most part 
agreed that forests should be owned by some public body, 
national, state or local political unit, although an important place 
is also found for private ownership. But for the great bodies of 
water, covering more than half of the earth’s surface, the nations 
of the world reject the idea of either public or private ownership, 
and stand for the idea that the seas are free, common, ownerless 
goods, like the air we breathe. On the other hand, the experience 
of the world and the nature of the case speak overwhelmingly for 
private ownership of purely agricultural land. Thus, not even 
one problem in land utilization, such as ownership, can be 
handled satisfactorily without consideration of the different kinds 
of land. 
Another statement that we hear is that land should be brought 
into use: and it is proposed by some to tax land to the point of